211861360656 has 225 divisors, whose sum is σ = 654269184205. Its totient is φ = 63997887360.

The previous prime is 211861360597. The next prime is 211861360681. The reversal of 211861360656 is 656063168112.

The square root of 211861360656 is 460284.

It is a perfect power (a square), and thus also a powerful number.

211861360656 is a `hidden beast` number, since 21 + 1 + 8 + 6 + 13 + 606 + 5 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11859210000 + 200002150656 = 108900^2 + 447216^2 .

It is a super-2 number, since 2×211861360656² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 668332210 + ... + 668332526.

Almost surely, 2^211861360656 is an apocalyptic number.

211861360656 is the 460284-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211861360656

211861360656 is an abundant number, since it is smaller than the sum of its proper divisors (442407823549).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

211861360656 is an frugal number, since it uses more digits than its factorization.

211861360656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692 (or 333 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 211861360656 in words is "two hundred eleven billion, eight hundred sixty-one million, three hundred sixty thousand, six hundred fifty-six".